public static RenderedProjectionDefinition <TProjection> Translate <TDocument, TProjection>(Expression <Func <TDocument, TProjection> > projector, IBsonSerializer <TDocument> parameterSerializer)
{
var parameterSerializationInfo = new BsonSerializationInfo(null, parameterSerializer, parameterSerializer.ValueType);
var parameterExpression = new SerializationExpression(projector.Parameters[0], parameterSerializationInfo);
var binder = new SerializationInfoBinder(BsonSerializer.SerializerRegistry);
binder.RegisterParameterReplacement(projector.Parameters[0], parameterExpression);
var normalizedBody = Normalizer.Normalize(projector.Body);
var evaluatedBody = PartialEvaluator.Evaluate(normalizedBody);
var boundExpression = binder.Bind(evaluatedBody);
var candidateFields = FieldGatherer.Gather(boundExpression);
var fields = GetUniqueFieldsByHierarchy(candidateFields);
var serializationInfo = fields.Select(x => x.SerializationInfo).ToList();
var replacementParameter = Expression.Parameter(typeof(ProjectedObject), "document");
var translator = new FindProjectionTranslator(projector.Parameters[0], replacementParameter, fields);
var newProjector = Expression.Lambda <Func <ProjectedObject, TProjection> >(
translator.Visit(boundExpression),
replacementParameter);
BsonDocument projectionDocument;
IBsonSerializer <TProjection> serializer;
if (translator._fullDocument)
{
projectionDocument = null;
serializer = new ProjectingDeserializer <TDocument, TProjection>(parameterSerializer, projector.Compile());
}
else
{
projectionDocument = GetProjectionDocument(serializationInfo);
var projectedObjectSerializer = new ProjectedObjectDeserializer(serializationInfo);
serializer = new ProjectingDeserializer <ProjectedObject, TProjection>(projectedObjectSerializer, newProjector.Compile());
}
return(new RenderedProjectionDefinition <TProjection>(projectionDocument, serializer));
}
